utils channel: Let channel_select() set errno.

diff --git a/src/utils/channel.c b/src/utils/channel.c
index 92d793e468c441b044c24d76bedd2d9dc51510f0..afce6f5d9cc9aa883afb9569aef9a384c433eb01 100644 (file)
--- a/src/utils/channel.c
+++ b/src/utils/channel.c
@@ -29,6 +29,8 @@
 
 #include <assert.h>
 
+#include <errno.h>
+
 #include <stdlib.h>
 #include <string.h>
 
@@ -170,11 +172,15 @@ sdb_channel_select(sdb_channel_t *chan, int *wantread, void *read_data,
        struct timespec abstime;
        int status = 0;
 
-       if (! chan)
+       if (! chan) {
+               errno = EINVAL;
                return -1;
+       }
 
-       if ((! wantread) && (! read_data) && (! wantwrite) && (! write_data))
+       if ((! wantread) && (! read_data) && (! wantwrite) && (! write_data)) {
+               errno = EINVAL;
                return -1;
+       }
 
        if (timeout) {
                if (clock_gettime(CLOCK_REALTIME, &abstime))
@@ -210,7 +216,11 @@ sdb_channel_select(sdb_channel_t *chan, int *wantread, void *read_data,
        }
 
        pthread_mutex_unlock(&chan->lock);
-       return status;
+       if (status) {
+               errno = status;
+               return -1;
+       }
+       return 0;
 } /* sdb_channel_select */
 
 int